Atomic quadrupole moments:np2(n+1)sexcited-state configuration of N, P, As, and Sb

The author has calculated the Sternheimer shielding factor pertaining to the atomic quadrupole moment for N, P, As, and Sb in the $n{p}^2\mathrm{}(n+1\mathrm{})s$ electronic configuration. The calculated values are 0.94, 1.25, 1.29, and 1.59, respectively. The results suggest that it is essential to incorporate the Sternheimer factor in theoretical calculation of the interactions involving the atomic quadrupole moment, e. g., the long-range ionquadrupole interaction as studied in recent merged-beam experiments.